It is contemplated by the inventor herein that all valves of the human body can be replaced by the inventive devices set forth herein eventhough heart valves are set forth primarily to describe the inventive device use.
Heart valve replacement surgery conventionally involves a full median sternotomy incision. Due to the invasiveness of this approach, medical referral culture for valve surgery has historically followed a policy of delay and observation until patient symptoms are advanced; despite well accepted guidelines that outline the benefit of earlier treatment of valvular heart disease. Recently, less invasive or “minimally invasive” approaches to valve surgery can be performed with equal or superior long term results. This represents one of the most significant recent market advances of valvular therapy. Patients and their physicians that are exposed to the renewed understanding of the concerns of delaying valve surgery now have a newer option that is swinging the referral patterns to earlier surgery and thus increasing volumes in many centers that focus on minimally invasive valve surgery.
Minimally invasive approaches to surgical valve replacement therapy have been performed via mini sternotomy yet a growing majority are currently being performed with access between the rib cage via a mini-right thoractomy. These procedures are often aided by femoral or endo-direct cannulation and port access techniques. As instrumentation improves, the principle working incision has the ability to further reduce in size in a step-wise manner towards the near future goal of total endoscopic therapy. Industry improvements in cannulation and instrumentation are proceeding at an exponential rate while market-ready valve repair and replacement design has lagged significantly behind. Currently, the principle factor for dictating incision size in current minimally invasive valve techniques is the size and immobility of available valve prostheses.
Current stented biologic tissue valve design principles include fixed bovine or porcine tissue affixed to a flexible textile material sleeve which is in turn attached to a rigid stent composite of moldable plastic which in some cases may include wire reinforcement, and a fixed malleable, plastic, flexible textile material sewing ring.
The design of an ideal tissue valve for minimally invasive surgical implantation should include improvements of the current commonly used stented tissue valves to address the following: Transcorporeal (traversing the body surface) low profile delivery, intracorporeal (inside the body) stabilization for suture placement, and minimal change to current valve replacement surgical implantation techniques in order to enhance surgical adoption while maintaining procedural effectiveness and safety.
The following for the modification of, but not limited to, biologic tissue prostheses addresses each of these areas while minimally altering current tissue valve production and preservation methods.
The human heart has four valves that control the direction of blood flow through the four chambers of the heart. On the left or systemic side of the heart are the mitral valve, located between the left atrium and the left ventricle, and the aortic valve located between the left ventricle and the aorta. On the right or pulmonary side of the heart are the tricuspid valves, located between the right atrium and the right ventricle, and the pulmonary valve, located between the right ventricle and the pulmonary artery.
For purposes of this invention, therapeutic utility is feasible with all valve positions and pathologies requiring replacement included herein eventhough this disclosure and discussion will primarily reference aortic and mitral replacement.